I totally get a chuckle out of it-out of the sheer absurdity and ridiculousness of it. That's the point of the sequence and Raimi knew this. I think he concsiously went against audience expectations.

The fanboys complain that it should've been darker and more serious, as though the dancing was the problem-but if the rest of the script was up to par, I think the dancing sequences could still have worked to great effect. Much like the raindrops sequence in SM2.

But as it is, the humourous sequences only exacerbated the other problems in the script, and is now blamed as the sole reason for SM3s failures.